PRESSURE VARIATION OF THE ELECTRICAL-CONDUCTIVITY OF DOLOMITE [CAMG(CO3)(2)]

The conductivity of dolomite is a decreasing function of pressure, ind icating that the dominant mechanism is ionic in alkaline earth carbona tes. The activation volume upsilon(act) at room temperature is obtaine d. The curvature observed in the logarithm of the conductivity versus pressure plot is discussed in terms of the activation of multiple mech anisms upon pressure or to the pressure dependence of upsilon(act). Th e estimation of the migration volume upsilon(m) from ionic thermocurre nt results through the cB Omega point defect parameter model yields to the evaluation of the association volume upsilon(alpha).